Methods of forming patterns commonly used in the related art may include a photolithography method, an imprint lithography method, a roll printing method, and the like.
The photolithography method is a method of manufacturing a pattern by forming a photoresist layer on a substrate and subsequently, performing exposure and development processes on photoresist layer. In the method, a circuit line width or a pattern line width may be determined due to a wavelength of light used in the exposure process. However, in consideration of the state of current technology, in the case of the photolithography method, it may be difficult to form a fine pattern on a substrate due to the interruption of light. Further, in order to form a micro-fine pattern, the initial investment costs for purchasing expensive exposure equipment and the like may be increased, and the price of high resolution masks has rapidly increased, thereby leading to the deterioration of efficiency in manufacturing costs. In addition, every time the pattern is formed, it may be necessary to perform an exposure process, a baking process subsequent to the exposure process, a development process, a baking process subsequent to the development process, an etching process, a cleansing process, and the like. Thus, since a relatively long processing time may be required and multiple photo processes need to be repeated, problems such as deteriorations in productivity may be encountered.
The imprint lithography method is a method initially developed by Stephen Y. Chou at Princeton University, in order to imprinting a nanoscale pattern. In the method, a desired shape is fabricated in advance on a surface of an inorganic surface or a polymer having relatively high strength. The shape is subsequently stamped on another material, thereby forming a pattern. In more detail, the imprint lithography method is a method of attaching an inorganic or polymer mold provided with a desired pattern to a curable composition coated on a metal film or an organic film and then applying heat thereto, or performing a photocuring process thereon, to thereby form a pattern. As compared to the photolithography method, the imprint lithography method may allow for a simple process and may be advantageous in forming a fine pattern.
The roll printing method is concretely disclosed in Korean Patent Laid Open Publication No. 2007-0076292 (Jul. 24, 2007). In the rolling printing method, a direct pattern transfer may be formed on a substrate on which fine patterns will be formed, using a silicone polymer and a cliché, instead of a high solution mask used in the formation of patterns in existing photolithography processes. In the roll printing method, a silicone polymer may be used as a stamp to improve alignments and releasability with a mold, and a thermosetting process may be used to increase productivity and operation efficiency. In addition, the roll printing method has been proposed as an alternative method capable of dramatically simplifying and reducing the complexity of several processes such as exposure and development processes, and the like in the photolithography method, and correspondingly caused additional processing costs.
However, in the case of the photolithography method, the imprint lithography method, and the roll printing method according to the related art, in forming a pattern having a desirable width and thickness, for example, a fine pattern having a high aspect ratio, limitations may be present in terms of ease of manufacturing, precision of formed patterns, and easy repeatability of a pattern formation process. Thus, the development of a novel method of forming various patterns having a desired width and thickness is required.